<!doctype html>
<html lang="en">
	<head>
		<meta charset="UTF-8" />
		<meta name="viewport" content="width=device-width, initial-scale=1.0" />
		<title>关系选择器之交集选择器</title>
		<style type="text/css">
			/*p.tag代表p标签选择器和类选择器的交集*/
			p.tag{
				color: red;
			}
		</style>
	</head>
	<body>
		<h1 class="tag">我是标题</h1>
		<p class="tag">我是个p</p>
		<p id="title">我是个p</p>
	</body>
</html>
